Q140032: BUG: After Switching OLE Client Hangs in Visual Basic 16-Bit

Article: Q140032
Product(s): Microsoft Visual Basic for Windows
Version(s): 4.0
Operating System(s): 
Keyword(s): kbbuglist
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SYMPTOMS
========

When you create an OLE server program and an OLE client program in the 16-bit
edition of Visual Basic for Windows, version 4.0 and run both programs, the
client program stops responding after switching from the OLE server program back
to the OLE client program.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. Microsoft is researching this problem and will post
new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION
================

Steps to Reproduce Problem
--------------------------

1. Start the 16-bit version of Visual Basic 4.0, or if it is already running,
  click New Project on the File menu.

2. Use the following steps to create an OLE server called MyPop:

  a. On the menu, click Tools.

  b. On the Tools menu, click Options, and then click the Project tab.

  c. In the Project Name text box, type "MyPop." In the StartMode group, click
     OLE server. In the Application Description text box, enter Pop OLE server.

  d. Click OK to close the Options dialog box.

3. Use the following steps to create a class module:
  a. On the menu, click Insert. On the Insert submenu, click Class Module. The
     code window for the Class1 class module appears.

  b. In the Properties window of the Class1 class module, set the Instancing
     Property to 2-Creatable MultiUse, and set the Public property to True.

4. Add the following code to the Class1 code window:

         Private Sub Class_Initialize()
            Beep
         End Sub

         Private Sub Class_Terminate()
            Stop
         End Sub

5. Add a label to Form1. Set the Caption of this label to "My OLE Server."

6. Press the F5 key to start the program. Minimize this instance of Visual
  Basic.

7. Start a second instance of Visual Basic 16-bit. In the Project window, Form1
  is highlighted.

8. On the File menu, click Remove File to remove Form1.

9. On the Insert menu, click Module to create a module. The code window for
  Module1 is displayed. Add the following code to the Module1 code window:

         Sub Main()
            goo
         End Sub

10. Create another module and add the following code into the Module2 code
  window:

         Sub goo()
            Set r = New Class1
            Set r = Nothing
         End Sub

11. On the Tools menu, click References. The References dialog box is displayed
  with a list of all the objects that are available from other applications.
  In the Available References list box, scroll down the list until the Pop OLE
  Server check box is displayed. Click this check box. Click OK to close the
  References dialog box.

12. Press the F8 key to single step through the program until you get to the
  Stop statement.

13. Press ALT+TAB to return to the client. The client program stops responding.

Additional query words: vb4win vb416 buglist4.00 hung hang

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Keywords          :  kbbuglist
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : :4.0
Issue type        : kbbug

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